Broadcast receiver not working when app is closed

Question

So I have two different apps made, one sends a broadcast and another receives it and displays a toast. However, when I close the receiver app the broadcast is no longer received by the second app even though I defined the receiver in the manifest file.

The broadcast sender in the MainActivity of app1.

public class MainActivity extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    Button b = (Button)findViewById(R.id.button2);
    b.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent i = new Intent();
            i.setAction("com.example.ali.rrr");
            i.addFlags(Intent.FLAG_INCLUDE_STOPPED_PACKAGES);
            sendBroadcast(i);
            Log.e("Broadcast","sent");
        }
    });
}

App 2 broadcast receiver:

public class MyReceiver extends BroadcastReceiver {

@Override
public void onReceive(Context context, Intent intent) {
    // TODO: This method is called when the BroadcastReceiver is receiving
    // an Intent broadcast.
    Toast.makeText(context, "Broadcast has been recieved!", Toast.LENGTH_SHORT).show();
    Log.e("SUCCESS", "IN RECIEVER");
    //throw new UnsupportedOperationException("Not yet implemented");
}

App 2s Manifest:

<?xml version="1.0" encoding="utf-8"?>

<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:roundIcon="@mipmap/ic_launcher_round"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">
    <receiver
        android:name=".MyReceiver"
        android:enabled="true"
        android:exported="true">
        <intent-filter>
            <action android:name="com.example.ali.rrr" />
        </intent-filter>
    </receiver>

    <activity
        android:name=".MainActivity"
        android:label="@string/title_activity_main"
        android:theme="@style/AppTheme.NoActionBar" />
    <activity
        android:name=".Main2Activity"
        android:label="@string/title_activity_main2"
        android:theme="@style/AppTheme.NoActionBar">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
</application>

Answer 1

After registering my BroadcastReceiver (BR) statically in the manifest, applying the proper intent filters, using JobIntentService (and registering it in the manifest) to handle the work that was called from my BR, I was still getting inconsistent results.

Once all of what I listed above has been done you should be able to send an ADB command to activate your broadcast and process the work in your service even if the app is closed. This was working for me some of the time, but not all of the time.

This article describes limitation to BRs. "As of Android 3.1 the Android system excludes all receiver from receiving intents by default if the corresponding application has never been started by the user or if the user explicitly stopped the application via the Android menu" (AKA a user executes Force Stop)

When I start the app by debugging it, then swipe it closed on my device, my ADB command never activates my BR. However, after my debugging session is over, when I open up the app on my device and swipe it closed, I can activate my BR through ADB commands.

This occurs because when you debug an application, then manually swipe it closed on the device, Android considers this a Force Stop hence why my BR cannot be activated until I re-open the app on the device without debugging.

Scoured the internet for hours, and wasn't able to find my solution, so I thought I'd post it here just in case some poor unfortunate soul is encountering the same weird functionality I was.

Happy coding :)

Answer 2

First of all you need to use the Service for this functionality to work.

In the Activity you can start and stop the service by using the below codes.

// to start a service
Intent service = new Intent(context, MyBrodcastRecieverService.class);
context.startService(service);

// to Stop service
Intent service = new Intent(context, MyBrodcastRecieverService.class);
context.stopService(service);

Then you can use the below service

public class MyBrodcastRecieverService extends Service
{
    private static BroadcastReceiver br_ScreenOffReceiver;

    @Override
    public IBinder onBind(Intent arg0)
    {
        return null;
    }

    @Override
    public void onCreate()
    {
        registerScreenOffReceiver();
    }

    @Override
    public void onDestroy()
    {
        unregisterReceiver(br__ScreenOffReceiver);
        m_ScreenOffReceiver = null;
    }

    private void registerScreenOffReceiver()
    {
        br_ScreenOffReceiver = new BroadcastReceiver()
        {
            @Override
            public void onReceive(Context context, Intent intent)
            {
                Log.d(TAG, "ACTION_SCREEN_OFF");
                // do something, e.g. send Intent to main app
            }
        };
        
        IntentFilter filter = new IntentFilter(Intent.ACTION_SCREEN_OFF);
        registerReceiver(br_ScreenOffReceiver, filter);
    }
}